New submission from Bruno P. Kinoshita <brunodepau...@yahoo.com.br>:
Hi, Tested on Python 3.7 on Ubuntu LTS. But I believe this affects previous versions too, as found it from an issue posted in Jinja2 in 2013: https://github.com/pallets/jinja/issues/276 This code simulates the issue where the traceback has the wrong line number (without using any Jinja2 code): ``` class Z(object): def __str__(self): raise ValueError('Z error') def raise_generator(): yield 'three values are: %s %s %s' % ( 'primeiro', Z(), # traceback must point to this lineno 9 'terceiro' # but points to this lineno 10 (__str__ only, __eq__ is OK) ) print(list(raise_generator())) ``` The output: ``` Traceback (most recent call last): File "/home/kinow/Development/python/workspace/cylc-flow/cylc/flow/tests/Z.py", line 14, in <module> print(list(raise_generator())) File "/home/kinow/Development/python/workspace/cylc-flow/cylc/flow/tests/Z.py", line 10, in raise_generator 'terceiro' # but points to this lineno 10 (__str__ only, __eq__ is OK) File "/home/kinow/Development/python/workspace/cylc-flow/cylc/flow/tests/Z.py", line 3, in __str__ raise ValueError('Z error') ValueError: Z error ``` Jinja uses something similar to the class Z to raise errors when the template has undefined variables. The curious part is that if instead of simply formatting the string with "%s" % (Z()) you use "%s" % (str(Z())) or if you callZ().__str__(), then the traceback reports the correct line number. Not sure if intentional, but would be nice if the traceback reported the correct line number, and I think other applications could end up having the same issue. This is my first issue, so I apologize if I did not include enough information, or if there is anything missing in this ticket. Let me know if I need to update it with more information or formatting the code. Would be happy to work on this if this is considered an easy-to-fix issue. Thanks all for your work on Python, Bruno P. Kinoshita ---------- components: Interpreter Core messages: 348277 nosy: kinow priority: normal severity: normal status: open title: Wrong lineno in traceback when formatting strings with % and multilines type: behavior versions: Python 3.7 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue37647> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
